1. Field of the Invention
The subject invention generally relates to a steering column assembly for a vehicle, and more specifically to a steering column assembly adjustable in both a rake direction (tilt) and a telescope direction.
2. Description of the Prior Art
Typically, steering column assemblies adjustable in a rake direction and a telescoping direction rely on a friction locking system to maintain a selected position of adjustment during normal operation. However, the friction locking system does not provide a positive mechanical lock preventing movement in the rake direction and the telescope direction under extreme impact conditions. It is important to maintain the selected position of adjustment during the extreme impact conditions to optimize the operation of an energy absorption device incorporated into the steering column assembly, which absorbs energy transmitted through the steering column assembly.
Accordingly, positive mechanical locking systems have been incorporated into the adjustable steering column assemblies to maintain the selected position of adjustment during the extreme impact conditions. U.S. Pat. No. 6,616,185, Ser. No. 10/177,182, discloses a steering column assembly having a locking system of interlocking teeth to maintain the selected position of adjustment during the extreme impact conditions. The interlocking teeth are in a disengaged position during normal operation of the vehicle and move into an engaged position during an extreme impact condition to positively lock the rake adjustment and the telescopic adjustment of the steering column assembly. However, there is still some movement of the steering column assembly in both the rake direction and the telescope direction as the interlocking teeth move from the disengaged position into the engaged position.